The invention relates to a locking device for a valve, and in particular, locking device for a shut-off valve on a fluid meter yoke that protects the shut-off valve and the hasp of a lock used in conjunction with the locking device from damage, vandalism and the like.
A public utility company, such as a gas or a water company, uses a meter to determine customer usage. If a customer is delinquent in paying the bill, the utility may terminate service and remove the meter thereby preventing the lawful use of the utility services.
Some customers will resort to unlawful means to gain access to utility service. One common way has been to defeat any locks that have heretofore been used to prevent usage. Past locks have been particularly subject to defeat as exemplified by the patents discussed below.
The patent art has disclosed locking devices for valves and the like. For example, U.S. Pat. No. 566,932 to Patrick is directed to stop-cock lock which is stated to be simple and durable in construction and easily applied or removed. The Patrick device consists principally of a slotted hasp adapted to be passed around the stop-cock and engage with its slot the turn-key of the cock. The free ends of the hasp are adapted to be locked together. One major drawback of the structure depicted in the Patrick patent is that the hasp of the lock is exposed. In other words, one who wants to defeat the lock has direct effective access with a saw blade or the like to the hasp so as to be able to saw the hasp in two thereby defeating the lock and gaining access to the valve.
Another example from the patent art is U.S. Pat. No. 1,780,994 to Caldwell. Caldwell is directed to a device for sealing or locking valves or cocks by providing a box-shaped member arranged to snuggly fit two opposite sides and the base of a valve or cock and includes two hinged lids arranged to fold down upon and interlock with the projecting stem or key of the valve or cock. The structure depicted in the Caldwell patent suffers the same drawback as Patrick in that the hasp of the lock is directly accessible by a saw blade or the like whereby the hasp can be sawed in two and the lock defeated. By defeating the lock, one gains access to the valve.
Still another example from the patent art is U.S. Pat. No. 2,924,960 to Palazzo which is directed to a lock engageable with a valve stem so as to prevent operation of the valve by unauthorized individual. Again, the device depicted in the Palazzo patent shows that one can have effective direct access by a saw blade to the hasp of the lock thereby permitting one to saw the hasp in two and defeat the lock.
U.S. Pat. No. 3,156,256 to Weaver is directed to a detachable valve locking means for valves of gas, water, or like pipes wherein it is desirable to maintain the valve in either an open or closed condition against unauthorized actuation. It is apparent that the device depicted in Weaver does not prevent effective direct access by a saw blade to the hasp of the lock. It seems the device depicted in Weaver can be defeated.
U.S. Pat. No. 4,162,690 to Anderson is directed to a locking device which includes a handle assembly and locking member which cooperate with an abutment member mounted on a valve housing to secure a valve in either an open or closed position. The device depicted in the Anderson patent does not effectively prevent direct access to the hasp by a saw blade, and thus, the structure is accessible to defeat by sawing the hasp in two.
Therefore, it becomes readily apparent that there is need for a locking device for shut-off valve, meter or the like that provides protection to both the shut-off valve and the lock used in conjunction therewith. By providing a locking device offering such protection, the integrity of the locking device is increased. This results in a decrease of unauthorized use of utility services.